Rationale:
Our institution began using the Globus ExcelsiusGPS robot in 2023 after its approval for cranial use by the FDA in 2021. The robot was used for epilepsy surgeries, including placement of depth electrodes, laser ablation (LITT), placement of Neuropace (RNS), and placement of deep brain stimulator (DBS). Across 59 epilepsy surgeries performed on 38 patients over our first two years, we have used the robot for 467 trajectories. Surgery time, accuracy of trajectory, and hemorrhage rate were analyzed in this study to determine influencing factors.
Methods:
We performed a retrospective chart review of epilepsy surgeries performed using the Globus ExcelciusGPS Cranial Robot over the first two years of experience in our hospital. Variables analyzed to determine their influence on surgery include the length of surgery, the number of cases performed, the number of trajectories placed, the surgery type, the time required to place each electrode, and the accuracy of electrode placement. We also analyzed hemorrhage rate depending on surgery type. Pearson correlation and analysis of variance statistics were used.
Results:
The amount of time each surgery required decreased as more cases were performed (p< 0.05, Figure 1), indicating that surgeries got faster with experience. Surgery time increased as the number of trajectories per case increased (p< 0.01) because it took longer to place more electrodes or lasers. The type of surgery influenced the time required to place each electrode (p< 0.001), with LITT surgeries taking the longest and SEEG taking the least amount of time. There was also a difference in accuracy based on surgeon assisting (p< 0.001). For SEEG surgeries, the accuracy of electrode placement correlated with the number of surgeries done by the surgical assistant (p< 0.05, Figure 2). The hemorrhage rate for DBS and RNS was 0% while the hemorrhage rate for SEEG was 0.7% per electrode and 10% per surgery. None of the hemorrhages during SEEG surgery were symptomatic. The hemorrhage rate for LITT was 15% per laser and 21% per case with a 7% rate of neurological symptoms from hemorrhage per case.
Conclusions:
These findings indicate that with experience, surgeries utilizing the Globus ExcelsiusGPS robot become faster and more accurate, and that the accuracy of surgery can vary depending on the robot’s user. The type of surgery performed influences the amount of time required for a surgery. These surgeries remain relatively safe given the low rate of symptomatic hemorrhage with DBS and RNS having the lowest rate and LITD having the highest. These findings might be used to improve epilepsy surgery efficiency and accuracy using the Globus ExcelciusGPS robot.
Funding: Internal Inova grant funds.